All the labels are just so nonsensical. I did a little bit of digging into how cross-site tracker blocking is implemented in Firefox, and it took me a while to realize that switching from Standard to Strict ETP in a fresh profile was all I needed to do to beat the EFF's test site.
But the options under ETP still confuse me. Take the Custom > Cookies section.
Blocking all cookies - makes sense
Blocking all third party cookies - ditto, only cookies from the current site will be allowed
Cookies from unvisited sites - this one is a little weird. So if I've been to Google once, does that mean I can get cookies from google.com but not ads.google.com?
Isolate cross-site cookies - so third party cookies aren't blocked, but for each site that uses the same third party, the third party cookie is different?
Cross-site and social media trackers - I have no idea. Sounds like the last one (which should cover everything?) and maybe block social media cookies entirely?!
There's also the "tracking content" which appears to be the only thing that is blocked in ETP strict but not ETP standard. I have to assume this is some blacklist of known tracking scripts or something.
It's a lot to wrap my head around. It really could use a checklist.